The present invention relates to apparatus for comminuting tobacco, and more particularly to tobacco shredding apparatus. Still more particularly, the invention relates to improvements in tobacco shredding apparatus of the type disclosed in commonly owned U.S. Pat. No. 4,037,712 to Wochnowski.
The patent to Wochnowski discloses a shredding apparatus wherein an upright duct receives tobacco at a constant or substantially constant rate and admits tobacco into the space between two convergent chains which convert the tobacco particles into a cake and feed the leading end of the cake into the path of orbiting knives. The speed of the motor for the chains and for the knives is varied in dependency on changes of the volume of tobacco in the duct. Such apparatus are quite satisfactory. However, they cannot be incorporated into or combined with the machines of certain existing tobacco processing production lines. This is due to the fact that the existing production lines employ a wide variety of tobacco feeding devices, and the mode of operation of such feeding devices is based on different principles. Furthermore, the output of recent types of tobacco shredding apparatus is a multiple of the output of apparatus which, only a few years ago, were standard components of tobacco processing production lines. Therefore, the time allotted for the making of a satisfactory cake which is thereupon fed into the range of comminuting instrumentalities is extremely short. This, in turn, renders it necessary to insure uninterrupted satisfactory feed of tobacco into the space between the compacting chains. Finally, and since the shredding apparatus constitutes but one component of a long line of cooperating machines, and since the output of certain machines of the production line often fluctuates within a wide range, the shredding apparatus must be sufficiently flexible to immediately react to changes in delivery of tobacco thereto and/or to changes in the requirements of machine or machines which receive shredded tobacco therefrom.
A drawback of all presently known shredding apparatus is that the conditions under which the apparatus operate at an optimum rate cannot be altered to a substantial degree without affecting the quality of the product. Otherwise stated, the quality of the product is overly dependent on the condition, mode of operation and/or other parameters of the machine or machines which precede the shredding apparatus in existing production lines. Thus, even the operation of the aforementioned patented apparatus of Wochnowski is or can be strongly affected by fluctuations in the rate of delivery of tobacco to its duct. Furthermore, many presently known shredding apparatus exhibit the drawback that the existing controls which are employed to counteract the effect of fluctuations of the rate of tobacco feed often aggravate the situation, especially when the fluctuations of the rate of delivery are attributable to unpredictable parameters, such as changes in the size, moisture content and/or temperature of tobacco.